"All I know is that we signed a contract with our agent and that he could not find a security company for us."

The orchestra was due to perform in cities including Los Angeles, San Francisco and Chicago, but is planning to go ahead with other concerts in Australia and Taiwan.

Orchestra chairman Zeev Dorman told Israeli radio: "We have never before experienced a cancellation of this kind.

"Usually cancellations are the result of funding problems - as in they could not sell enough tickets. But in this case, security is the official reason they gave us."

The orchestra performed in the United States in January without any problems, Mr Shoshani said.

Cancellations

They have also been hit by problems resulting from the threat of violence at home.

Half of the foreign artists due to appear with the orchestra in Israel had cancelled their trips due to the increased volatility in the region, Zubin Mehta, the orchestra's music director told the Washington Post.

"In the current production of Richard Strauss's opera Salome, we've had eight cancellations in the cast," he said.

The Israel Philharmonic Orchestra was created in 1947, with Leonard Bernstein as its Laureate Conductor for more than 40 years until his death in 1990.